<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<script>
var p =prompt("请输入月份");

    if(p<5||p>10){
        console.log("淡季");
        var a = prompt("请选择头等舱还是经济舱");
        if (a==="头等舱"){
            console.log(800)
        }else {
            console.log(200)
        }

    }else{
        console.log("旺季");
        var b =prompt("请选择头等舱还是经济舱");
        if (a==="头等舱"){
            console.log(2000)
        }else{
            console.log(800)
        }
    }

</script>
</body>
</html>